Mushroomy Kingdom (which is supposed to be Mushroom Kingdom) is a stage in Super Smash Bros. Brawl. This state is one of the states that during all star mode, Mario, Luigi, Peach, and Bowser can appear on to fight. This stage has a lot of ? blocks, which when hit, can give players a few items. There are also a few hidden blocks inside the course, that do the same as the visable blocks.
There are two variations of this course. One is the above ground course, and there is an underground course also. The basic course that you can always go to is the above ground, with a chance of going to the underground. There is a way, though, to always go underground. To achieve this, one needs to hold in the z button before they select the course, and hold it through until the game loads.